Indexing terminal arrangement

ABSTRACT

An indexing terminal arrangement includes a terminal housing that receives an input cable; an optical power splitter disposed within the interior of the terminal housing; a first multi-fiber optical adapter coupled to the terminal housing; a first single-fiber optical adapter coupled to the terminal housing; and a pass-through multi-fiber optical adapter coupled to the terminal housing. Split optical signals are provided to the first multi-fiber optical adapter and the first single-fiber optical adapter. Unsplit and indexed optical signals are provided to the pass-through optical adapter.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation of U.S. patent application Ser. No.15/553,360, filed on Aug. 24, 2017, now U.S. Pat. No. 10,317,640, whichis a National Stage Application of PCT/US2016/019044, filed on Feb. 23,2016, which claims the benefit of U.S. Patent Application Ser. No.62/120,121, filed on Feb. 24, 2015, the disclosures of which areincorporated herein by reference in their entireties. To the extentappropriate, a claim of priority is made to each of the above disclosedapplications.

BACKGROUND

Passive optical networks are becoming prevalent in part because serviceproviders want to deliver high bandwidth communication capabilities tocustomers. Passive optical networks are a desirable choice fordelivering high-speed communication data because they may not employactive electronic devices, such as amplifiers and repeaters, between acentral office and a subscriber termination. The absence of activeelectronic devices may decrease network complexity and/or cost and mayincrease network reliability.

SUMMARY

Some aspects of the present disclosure are directed to an indexingterminal arrangement including a terminal housing configured to receivean input cable having multiple optical fibers; an optical power splitterdisposed within the interior of the terminal housing; a firstmulti-fiber optical adapter coupled to the terminal housing; a firstsingle-fiber optical adapter coupled to the terminal housing; apass-through multi-fiber optical adapter coupled to the terminalhousing; and a multi-fiber optical connector that is optically coupledto others of the optical fibers of the input cable. The optical powersplitter is configured to optically couple to one of the optical fibersof the input cable. The optical power splitter is configured to splitoptical signals carried by the optical fiber of the input cable onto aplurality of splitter pigtails. The first multi-fiber optical adapterdefines an interior port accessible from within the interior of theterminal housing and defines an exterior port accessible from theexterior of the terminal housing. Some of the splitter pigtails areoptically coupled to the interior port of the first multi-fiber opticaladapter. The first single-fiber optical adapter defines an interior portaccessible from within the interior of the terminal housing and definesan exterior port accessible from an exterior of the terminal housing.Another of the splitter pigtails is optically coupled to the interiorport of the first single-fiber optical adapter. The pass-throughmulti-fiber optical adapter defines an interior port accessible fromwithin the interior of the terminal housing and defines an exterior portaccessible from the exterior of the terminal housing. The multi-fiberoptical connector is plugged into the interior port of the pass-throughmulti-fiber optical adapter. Optical lines are indexed between theothers of the optical fibers of the input cable and fiber positions ofthe multi-fiber optical connector.

In certain implementations, multiple single-fiber optical adapters arecoupled to the terminal housing including the first single-fiber opticaladapter. Each of the splitter pigtails is separately routed to one ofthe single-fiber optical adapters.

In certain implementations, multiple multi-fiber optical adapters arecoupled to the terminal housing including the first multi-fiber opticaladapter. A first set of splitter pigtails are connectorized at a firstmulti-fiber connector that is plugged into a first of the multi-fiberoptical adapters. A second set of splitter pigtails are connectorized ata second multi-fiber connector that is plugged into a second of themulti-fiber optical adapters.

In certain implementations, another single-fiber optical adapter iscoupled to the terminal housing. An unsplit one of the optical fibers ofthe input cable is optically coupled to an interior port of thesingle-fiber optical adapter. The single-fiber optical adapter definesan unsplit output port accessible from the exterior of the terminalhousing. In an example, the unsplit one of the optical fibers of theinput cable is optically spliced to another optical fiber that isoptically coupled to the single-fiber optical adapter that defines theunsplit output port.

In certain implementations, the multi-fiber optical connector terminatesthe others of the optical fibers of the input cable.

In certain implementations, stub fibers of the multi-fiber opticalconnector are mass fusion spliced to the others of the optical fibers ofthe input cable.

In certain implementations, a first optical coupler is disposed withinthe terminal housing. The first optical coupler has a firstinput/output, a second input/output, and a third input/output. The firstinput/output is optically coupled to the optical fiber of the inputcable, the second input/output is optically coupled to the multi-fiberoptical connector, and the third input/output is optically coupled tothe optical power splitter. The third input/output receives any opticalsignals that are received at the first and second input/outputs.

In an example, the first optical coupler includes an optical powersplitter. The first and second input/outputs of the first opticalcoupler are power splitter outputs and the third input/output of thefirst optical coupler is a power splitter input.

In certain examples, the single-fiber optical adapters include eightsingle-fiber optical adapters. In certain examples, the multi-fiberoptical adapters include two multi-fiber optical adapters.

Other aspects of the present disclosure are directed to an indexingterminal arrangement including a terminal housing configured to receivean input cable having multiple optical fibers; an optical power splitterdisposed within the interior of the terminal housing; a plurality offirst hardened multi-fiber output ports disposed at the terminal housingand accessible from an exterior of the terminal housing; a plurality ofhardened single-fiber output ports disposed at the terminal housing andaccessible from an exterior of the terminal housing; and a multi-fiberpass-through port disposed at the terminal housing and accessible froman exterior of the terminal housing. The optical power splitter isconfigured to optically couple to one of the optical fibers of the inputcable. The optical power splitter is configured to split optical signalscarried by the optical fiber of the input cable onto a plurality ofsplitter pigtails. Each of the first hardened multi-fiber output portsis configured to receive a connectorized end of a multi-fiber cable toalign the connectorized end of the multi-fiber cable with aconnectorized end of a plurality of the splitter pigtails. Each of thehardened single-fiber output ports is configured to receive aconnectorized end of a single-fiber cable to align the connectorized endof the hardened single-fiber cable with a connectorized end of arespective one of the splitter pigtails. The multi-fiber pass-throughport is configured to receive a connectorized end of a multi-fiberpass-through cable to align the connectorized end of the multi-fiberpass-through cable with a multi-fiber connector that is opticallycoupled to unsplit optical fibers of the input cable, wherein a firstsequential position of the multi-fiber connector defines an activeoptical line.

In some implementations, the optical fibers of the input cable enter theterminal housing and wherein the terminal housing includes a gasket forenvironmentally sealing against the input cable. In otherimplementations, a multi-fiber optical adapter is coupled to theterminal housing so that an exterior port is accessible from an exteriorof the terminal housing. The exterior port is configured to sealinglyand robustly receive a connectorized end of the input cable.

In certain implementations, another single-fiber output port disposed atthe terminal housing and accessible from an exterior of the terminalhousing. The single-fiber output port is configured to receive aconnectorized end of a single-fiber cable that is aligned with asingle-fiber optical connector that receives unsplit optical signalsfrom one of the optical fibers of the input cable.

In certain implementations, the optical fibers of the input cable areoptically spliced to other optical fibers within the terminal housing.

In certain implementations, the optical fibers of the input cable thatare optically coupled to the multi-fiber connector are coupled using amass-fusion splice.

In certain implementations, the terminal housing includes a top and abottom that extending between a first end and a second end, the top andbottom also extend between a first side and a second side. The firsthardened multi-fiber output ports and the hardened single-fiber outputports are disposed at the top of the terminal housing. In certainexamples, the input cable is received at the first end of the terminalhousing.

In certain implementations, the hardened multi-fiber output ports areconfigured to receive HMFOC connectors and the hardened single-fiberoutput ports are configured to receive DLX connectors.

A variety of additional inventive aspects will be set forth in thedescription that follows. The inventive aspects can relate to individualfeatures and to combinations of features. It is to be understood thatboth the forgoing general description and the following detaileddescription are exemplary and explanatory only and are not restrictiveof the broad inventive concepts upon which the embodiments disclosedherein are based.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the description, illustrate several aspects of the presentdisclosure. A brief description of the drawings is as follows:

FIG. 1 is a block diagram showing an example indexing terminalarrangement that is configured to split and index optical lines receivedat the indexing terminal arrangement;

FIG. 2 is a block schematic diagram of the internal cabling of theindexing terminal arrangement of FIG. 1; and

FIG. 3 is a block diagram showing a portion of an example opticalnetwork including the indexing terminal arrangement of FIG. 1.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary aspects of the presentdisclosure that are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or like parts.

The present disclosure relates generally to an indexing terminalarrangement 100 including an optical power splitter. The indexingterminal arrangement 100 includes a housing 101 that is configured toreceive a multi-fiber input cable 102. In some implementations, thehousing 101 includes a compression seal arrangement or other sealingmechanism to enable the input cable 102 to enter the housing 101. Inother implementations, the housing 101 includes a hardened opticaladapter having a ruggedized outer port at which the input cable 102 canbe secured. As the term is used herein, a port is ruggedized if the portis environmentally sealed and enables a robust connection to an opticalconnected received thereat.

The indexing terminal housing 101 also defines a plurality of outputports at which various cables can be coupled. Each output port isdefined by an optical adapter supported by the housing 101. Each outputport is accessible from an exterior of the housing 101. Each opticaladapter defines at least one internal port accessible from an interiorof the housing 101. The housing 101 defines at least one output portconfigured to receive a single-fiber optical connector and at least oneoutput port configured to receive a multi-fiber optical connector. Inthe example shown, the indexing terminal housing 101 defines ninesingle-fiber output ports 104, 105 and three multi-fiber output ports106, 108.

As used herein, the terms “input” and “output” are not intended toindicate a direction in which all optical signals pass through thenetwork. Rather, the terms “input” and “output” are used forconvenience. Optical signals pass back and forth over optical linesbetween a central office and subscribers in an optical network. Incertain examples, one or more of the optical lines extend between twocentral offices or the same central office. Accordingly, optical signalspass over the input cable 102 both towards and away from the subscribersand central office(s). For the purposes of this disclosure, thesubscribers are considered to be downstream of a first central office inthe optical network.

The indexing terminal arrangement 100 indexes optical lines between theinput cable 102 and the output ports. For example, the input cable 102includes a plurality of optical fibers that each define part of oneoptical line. A first of the optical fibers of the input cable 102 isoptically coupled to the single-fiber output port to provide a firstoptical line to the single-fiber output port. Others of the opticalfibers of the input cable 102 are optically coupled to the multi-fiberoutput port, which defines a sequence of positions. The positions at themulti-fiber output port are filled in sequence so that optical lines areprovided from the input cable 102 to at least the first position.

FIG. 2 is a block schematic diagram illustrating internal cabling of theindexing terminal arrangement 100. The indexing terminal housing 101receives an input cable 102 having a plurality of optical fibers. In anexample, the input cable 102 has twelve optical fibers F1-F12. In otherexamples, the input cable 102 may have any desired number of fibers(e.g., four, six, eight, ten, etc.).

A first optical fiber F1 of the input cable 102 is optically coupled toa first single-fiber output port 105. In some implementations, the firstoptical fiber F1 has a connectorized end that is plugged into aninterior port of the first single-fiber output port 105. In otherimplementations, the first optical fiber F1 can be spliced (e.g., at asplice location 110) to a stub fiber connected at the first single-fiberoutput port 105. In still other implementations, the first optical fiberF1 can be optically coupled to a first optical coupler 120 (e.g., anoptical power splitter) as will be described in more detail herein. Forexample, the first optical fiber F1 can be optically spliced (e.g.,fusion spliced, mechanically spliced, etc.) to a first couplerinput/output fiber of the first optical coupler 120 at a splice location110. The first optical coupler 120 includes a second input/output fiberthat is routed to the first single-fiber output port 105.

A second optical fiber F2 of the input cable 102 is optically coupled toan optical power splitter 130, which splits any optical signals carriedby the second optical fiber F2 onto a plurality of splitter pigtails134. In some implementations, one or more of the splitter pigtails 134is routed to separate single-fiber output ports 104. For example, theone or more splitter pigtails 134 may each have a connectorized end thatplugs into the interior port of the respective single-fiber output port104. Accordingly, any optical signals carried by the second opticalfiber will be carried over any optical fiber cables plugged into any ofthe single-fiber output ports 104.

In some implementations, all of the splitter pigtails are routed toseparate single-fiber output ports 104. In other implementations, atleast some of the splitter pigtails 134 are routed to a multi-fiberoutput port 106. In certain examples, multiple splitter pigtails 134 arecommonly connectorized at a multi-fiber connector (e.g., an MPOconnector) that is plugged into an interior port of a multi-fiberadapter that defines the multi-fiber output port 106. In certainimplementations, the housing 101 holds a plurality of multi-fiberadapters that each define a multi-fiber output port 106. In the exampleshown, the housing 101 has two multi-fiber output ports 106. Some of thesplitter pigtails 134 are routed to a first of the multi-fiber outputports 106, others of the splitter pigtails 134 are routed to a second ofthe multi-fiber output ports 106, and still others of the splitterpigtails 134 are routed to separate single-fiber output ports 104.

In some implementations, the optical power splitter 130 has a 1×32 splitso that optical signals carried by the second optical fiber F2 are splitinto thirty-two splitter pigtails. In the example shown, twelve of thesplitter pigtails 134 are routed to the first multi-fiber output port106, another twelve of the splitter pigtails 134 are routed to thesecond multi-fiber output port 106, and the remaining eight splitterpigtails 134 are routed to separate single-fiber output ports 104. Inother implementations, the optical power splitter 130 has a 1×16 split,1×24 split, 1×48 split, 1×56 split, 1×64 split, 1×72 split, 1×96 split,1×128 split, or another desired split and an appropriate number ofsplitter pigtails 134 are routed to each port 104, 106.

In some implementations, the second optical fiber F2 has a connectorizedend that is plugged into an input port of the optical power splitter130. In other implementations, the second optical fiber F2 can bespliced (e.g., at a splice location 110) to a splitter input fiber. Instill other implementations, the second optical fiber F2 can beoptically coupled to a second optical coupler 120 (e.g., an opticalpower splitter) as will be described in more detail herein. For example,the second optical fiber F2 can be optically spliced (e.g., fusionspliced, mechanically spliced, etc.) to a first coupler input/outputfiber of the second optical coupler 120 at a splice location 110. Thesplitter input fiber is also coupled to the second coupler 120 (or asecond coupler input/output fiber is routed to the optical splitter130).

The third optical fiber F3 through twelfth optical fiber F12 of theinput cable 102 are optically coupled to another multi-fiber output port108 (i.e., a pass-through port). In some implementations, the thirdoptical fiber F3 through twelfth optical fiber F12 are connectorized ata multi-fiber connector 150 (e.g., an MPO connector) that is pluggedinto an interior port of a pass-through multi-fiber optical adapter,which defines the pass-through port 108. In other implementations, thethird optical fiber F3 through twelfth optical fiber F12 are opticallyspliced to stub fibers 155 of the multi-fiber connector 150. Forexample, the third optical fiber F3 through twelfth optical fiber F12may be spliced to the stub fibers 155 at a mass fusion splice 140.

In some implementations, the multi-fiber connector 150 defines aplurality of fiber positions. In certain examples, the number of fiberpositions of the multi-fiber connector 150 corresponds with the numberof fibers of the input cable 120. In the example shown, the multi-fiberconnector 150 defines twelve fiber positions P1-P12. However, thepositions P1-P12 do not correspond with the optical fibers F1-F12 of theinput cable 102. As noted above, the first and second optical fibers F1,F2 of the input cable 102 are routed to other output ports 104-106.Instead, the optical fibers F3-F12 of the input cable 102 are indexed ina first direction so that the third optical fiber F3 is routed to thefirst fiber position P1 of the connector 150. Subsequent fibers F4-F12are routed to the next available position in the sequence.

The last two fiber positions P11, P12 in the sequence do not receiveoptical fibers of the input cable 102. Rather, in some implementations,these fiber positions P11, P12 receive dead fibers (i.e., are notconnected to optical signal carrying lines that connect to the firstcentral office). In other implementations, a respective couplerinput/output fiber 125 extends between one of the optical couplers 120and one of the last two fiber positions P11, P12. Accordingly, eachcoupler 120 receives an optical line from the first central office (viathe input cable optical fiber F1, F2) and receives an optical line fromthe second central office (via the output port 108, multi-fiberconnector 150, and input/output fiber 125). Thus, optical signals fromeither central office can be provided to any of the other output ports104-106.

In some implementations, each of the single-fiber optical adapters 104,105 is a hardened optical adapter. In an example, the exterior port ofeach of the single-fiber optical adapters 104, 105 is configured toreceive a DLX connector. In some implementations, each of themulti-fiber optical adapters 106, 108 is a hardened optical adapter. Inan example, the exterior port of each of the multi-fiber opticaladapters 106, 108 is configured to receive an HMFOC connector.

FIG. 3 illustrates a portion of an optical fiber network including theindexing terminal arrangement 100. The input cable 120 is opticallycoupled to a central office 190 upstream in the optical network. Anothermulti-fiber cable can be received at the pass-through port 108 androuted to downstream portions of the optical network. In an example, thepass-through multi-fiber cable can be routed from the pass-through port108 to another indexing terminal arrangement 100 in the network. Inanother example, the pass-through multi-fiber cable can be routed fromthe pass-through port 108 to a central office 190. In still otherexamples, the pass-through multi-fiber cable can be routed to otherequipment in the network before reaching the central office 190 or otherindexing terminal arrangement 100.

Single-fiber subscriber cables 175 are routed from the single-fiberoutput ports 104 to subscriber locations 170. Multi-fiber distributioncables 185 are routed from the multi-fiber output ports 106 tomulti-service terminals 180, which define multiple output ports. One ormore fibers of the multi-fiber distribution cables 185 are opticallycoupled to single-fiber output ports of the multi-service terminals.Single-fiber subscriber cables 175 can be routed from the single-fiberports of the multi-service terminals to the subscribers 170. In certainimplementations, one or more of the multi-service terminals 180 caninclude an optical splitter, an optical splice tray, and optical fibermanagement disposed within the interior of the multi-service terminal180.

Having described the preferred aspects and implementations of thepresent disclosure, modifications and equivalents of the disclosedconcepts may readily occur to one skilled in the art. However, it isintended that such modifications and equivalents be included within thescope of the claims which are appended hereto.

What is claimed is:
 1. An indexing system comprising: a terminalhousing; an optical splitter disposed within the terminal housing, theoptical splitter being configured to split optical signals received at asplitter input onto a plurality of splitter outputs; a first multi-fiberconnection location; and a second multi-fiber connection locationlocated at the terminal housing; optical lines indexed between the firstand second multi-fiber connection locations; a first drop fiber beingoptically coupled to the first multi-fiber connection location and tothe input of the optical splitter; a second drop fiber being opticallycoupled to the second multi-fiber connection location and to the inputof the optical splitter; a third multi-fiber connection location at theterminal, the third multi-fiber connection location receiving some ofthe splitter outputs.
 2. The indexing system of claim 1, wherein thefirst multi-fiber connection location is disposed at the terminalhousing.
 3. The indexing system of claim 1, wherein the firstmulti-fiber connection location is ruggedized.
 4. The indexing system ofclaim 1, further comprising a fourth multi-fiber connection location atthe terminal, the fourth multi-fiber connection location receivingothers of the splitter outputs.
 5. The indexing system of claim 1,wherein the first drop fiber is optically coupled to the input of theoptical splitter via an optical splice.
 6. The indexing system of claim1, wherein the first drop fiber extends between the first multi-fiberconnection location and a coupler; and wherein the second drop fiberextends between the second multi-fiber connection location and thecoupler; and wherein an output of the coupler is optically coupled tothe input of the optical splitter.
 7. The indexing system of claim 6,wherein the output of the coupler is optically coupled to the input ofthe optical splitter via an optical splice.
 8. The indexing system ofclaim 1, wherein the second multi-fiber connection location is disposedwithin an interior of the terminal.
 9. The indexing system of claim 1,wherein the splitter outputs include connectorized splitter pigtails.10. The indexing system of claim 1, wherein the splitter outputs alsoinclude a single-fiber connection location.
 11. The indexing system ofclaim 10, wherein the splitter outputs also include a plurality ofsingle-fiber connection locations.
 12. The indexing system of claim 1,wherein the optical lines include a first set of optical fibersextending from the first multi-fiber connection location and a secondset of optical fibers that are spliced to the first set of opticalfibers.
 13. The indexing system of claim 12, wherein the second set ofoptical fibers extend from an intermediate multi-fiber connectionlocation disposed within the terminal, wherein the intermediatemulti-fiber connection location is optically coupled to the secondmulti-fiber connection location.
 14. The indexing system of claim 1,further comprising a third drop fiber being optically coupled to thefirst multi-fiber connection location and to a single-fiber connectionlocation.
 15. The indexing system of claim 14, further comprising afourth drop fiber being optically coupled to the second multi-fiberconnection location and to the single-fiber connection location.
 16. Theindexing system of claim 15, further comprising a coupler that receivesthe third and fourth drop fibers at an input and outputs to thesingle-fiber connection location.
 17. The indexing system of claim 15,further comprising an optical splice between the first multi-fiberconnection location and the second multi-fiber connection location. 18.The indexing system of claim 17, wherein the optical splice also couplesthe second multi-fiber connection location to the fourth drop fiber. 19.The indexing system of claim 1, wherein the third multi-fiber connectionlocation includes a multi-fiber adapter port.
 20. The indexing system ofclaim 1, wherein the second multi-fiber connection location includes amulti-fiber adapter port.